Research On Primary Frequency Modulation Control Technology Based On Electrochemical Energy Storage Technology

Primary frequency regulation is a dynamic frequency regulation method that stabilizes the grid frequency through the regulation of active power by the grid units.The energy storage power station can assist the grid to perform primary frequency regulation and maintain the stability of the grid frequency.The Yunnan power grid units cannot completely eliminate frequency oscillations during the primary frequency modulation process,resulting in power shortages and ultra-low frequency oscillations with a period of 20 s.The ultra-low frequency phenomenon causes great damage to the equipment of the power system.In order to solve this problem,this paper analyzes the research status of the ultra-low frequency oscillation problem and the development status of energy storage technology,and proposes a solution to the frequency stability problem after the asynchronous interconnection of the power grid by controlling energy storage.In order to solve the ultra-low frequency oscillation phenomenon in Yunnan power grid,this paper takes the chemical energy storage battery control model as the research object,studies the energy storage control model suitable for frequency modulation,and proposes an optimization scheme for the optimal capacity configuration of energy storage.First,by analyzing the status quo of Yunnan Power Grid,the cause of Yunnan ultra-low frequency oscillation is obtained,and the phenomenon of Yunnan Power Grid’s ultra-low frequency oscillation is simulated and analyzed.Then,the current source model that comes with DIGSILENT is selected to avoid the use of equivalent model method to build energy storage control.The model is not suitable for the disadvantages of complex power grids,and the effect of energy storage on the suppression of ultra-low frequency phenomena is verified on the small grid model;the predictive control method and the roulette selection method are used in the improved genetic algorithm to control the dead zone and control of energy storage.The adjustment coefficient is scrolled and optimized to obtain the optimal capacity configuration of energy storage;this optimization scheme is combined with two different parameter control methods(the control method with a larger dead zone and a smaller adjustment coefficient,and no action dead zone and A control method with a larger adjustment coefficient)is compared in the case of high fluctuation,low fluctuation,and stepped step signal frequency oscillation;finally,the energy storage control model is connected to the large power grid model for simulation verification.The results show that: in the primary frequency modulation,the electrochemical energy storage battery has a good suppression effect on the ultra-low frequency oscillation phenomenon.The energy storage configuration capacity obtained by rolling optimization can well meet the frequency modulation requirements,and the comparison and analysis of this optimization scheme and the fixed parameter control method of different parameters under different scene conditions show that this scheme has better multi-scenario adaptability and comprehensive adjustment performance.The verification result of the power grid model based on the data of Yunnan power grid on the control effect of energy storage shows that energy storage can not only shorten the time from frequency fluctuation to stability,but also reduce the peak value of frequency oscillation,which has a good suppression of ultra-low frequency oscillation.